When boxing fans converge on Las Vegas for the Floyd Mayweather-Conor McGregor fight this month, young women and children forced in to sex slavery will be brought into Sin City, according to a former CIA agent who now battles human trafficking. Huge sporting events create a big market for sex traffickers who appeal to men seeking sex with underage girls, said Tim Ballard, founder of Operation Underground Railroad. Ballard’s group works with law enforcement agencies to train police on how to spot human trafficking and rescue the victims.

You don’t have to travel to the Super Bowl or a Mayweather fight to find sex slaves, he said. They are help captive in your hometown, maybe in a massage parlor or a brothel, and moved from state to state on a circuit. Ballard and reporter Ninette Sosa join Nancy Grace on this Crimes Stories episode to discuss the problem.

Grace also updates the latest in Taylor Swift’s court battle with a Denver DJ over her allegation that he groped at a concert meet and greet backstage. David Mueller allegedly changed his explanation of what happened seven times, according to Swift’s lawyers. The singer is expected to take the stand to tell her story this week.

“Crime Stories with Nancy Grace” is now a national radio show, heard on SiriusXM’s Triumph Channel 132, five times a day. You can also subscribe and download the daily podcasts at iTunes and Google Play.